At present, cars, as one kind of the most commonly used transport means, have entered millions of households. With the popularization of cars, the driving safety problem is also getting more and more attention. One of the most common safety problems involves the blind areas formed by A pillars of a car. The A pillars are connecting pillars on the front left side and the front right side of the car for connecting the roof and the front cabin. For a car, pillars such as the A pillars not only have a supporting function but also play the role of door frame. However, the pillars produce visual blind areas for drivers, and this effect due to the A pillars is the most obvious. There is a dilemma for the width of an A pillar (affecting the cross section thereof). If the width is too small, the bearing capacity in unexpected situations will be advantageously affected, but if the width is too large, the user's field of view will be advantageously affected, which situations may therefore be detrimental to safety.